Superheater for water-tube boilers.



W. SCHMIDT da THOMSEN.

SUFERHEATER EUR WATER TUBE BUILERS.

APPLIUATUHI ILIzD PEB. 7. 1910.

l 90W?, ign@ 533.@ a Patented Sept. 23, 1913.

t Lowest.

parrain sfrafrns Parnnfrontricn,

WILHELM SCHMIDT AND PETER THOMSEN, 0F

MlANY, ASSIGNOBS T0 SCINEIDiSC-IE IEISSDAMPF GESELLSCHAFT, M. B. H., OFC

WILHELMSIIHE, NEAR CASSEL, GER- CASSEL, GERMANY, A CORPORATION 0F GERMANY.

SUPEBiHEATER FOR WATER-TUBE IBOILERS.

Specification of Letters Patent.

Patented Sept. 23, `ttlttft.

Application filed February 7, 1910. Serial No. 542,595.

To all whom 'it may concern Be it known that we, WILHELM SoHMnyr and Prana T noMsnN, subjects of the King of Prussia, Emperor of Germany, residing at lVilhelmshhe, near Cassel, Glermany, have invented certain'new and useful Improvements in Superheaters for later- Tube Boilers, of which the following is a specification.

Our invent-ionrelates'to water tube boilers and particularly to such boilers as are adapted for marine work. In such work many difficulties present themselves when attempt ing, an etiicient, economical and durable arrangementof parts owingto thelimited space wh'ih isnecessarily available, to the onces sive, st 'ainand jars towhich the part-s are subjected and to many other conditions well known to engineers practising in this art, ln vessels intended for naval purposes as for example battle ships, cruiscrstorpedo boats, etc., where the maximum amount of power and machinery must be installed in a minimum space, the difficulties aforesaid are greatly increased. `In avoiding thc difficulties peculiar to marine work, care must be taken atl the same time that the requirements necessary in good superheater practice generally, shall not be disregarded or slighted.

Itfis" the object of our invention to provide an arrangement of superheater and water tubeboiler, which shall be adapted to vessels of any-size and in which the very special requirements pertaining to marine practice shall be mety without in any way departing from the broad principles and ref quiremcuts usual in stationary practice.

t The nature of our present invention and its distinguishingf characteristics will be understood by reference to the description following and the drawings accompanying, in which- 4 Figure 1 represents a section through a preferred form of our invention; and Fig. 2 a similar section through a modified form thereof.

The general arrangement both in Figs. l and2 is that of a suitable superheater placed within a suitable flue, said flue being controlled by a damper and placed in 'iarallel with another tlue, whereby all or a ,certain propel tion of the fire gases may or may not,

as is desired, pass through said superlui-atrr flue. p

Referring to Fig. l; this represents a desirable construction for general marine practice. Here a central drum E is arranged symmetrically above a pair ot' gratos R and auxiliary drums F. These auxiliary drums F are connected to the main drum l by a central and two late `al sets of water tubes.

The central set of tubes is grouped in such a Way that on each side there is termed a flue A A bounded by walls a b of water tubes placed close together and haring opcnings at top and bottom for lhc entrance and egress of fire'gases. Each lateral group of water tubes is arranged to have in cach set thereof tiro flues BB and I) ll; these ilues are also bounded by water tube alla a (l, c j". Between B B `and l) D is a generous space in which-is placed a suitable supra heater u. At the lower end ol' cach superheatcr aY 1s a damper shown closed at` the right hand side of Fig. 1 and in open position'at the left hand side of the same figure. A similar damper l may be used at thc upper end of the superhcater it desired. Such a damper is shown at the right: hand side of Fig. 1, but omitted at the lefthand sido.

The operation of the superheater is as follows: lVhen steam is first to be started up, damper (and l, if the same be used) is closed. Fire gases then pass upwardly through flue A A' over the top of walls b and (f through flue B B and up and out by way ot' flue I) D', heater u has in this way received an initial charge of steam, the dampers K (and l., it used), may be opened. '1"his`results besides opening flue (l C in closing oli' to a great' extent, the lower end ot flue B y'B' sothat the tiro gases 'formerly all descending said l.

As soon as the super-` tio titl

tl U

I L' to (itl l El fi Sit,

7s and Z and the superheater guarded by them, to avoid burning out and excessive wear. When it is necessary to force the boiler, the temperature of the lire gases rises ot' course, but so does also the steam supply in about the saine proportion; for this reason the liability to burnsouts and execessive wea-r of parts is no greater under conditions ot' forced supply than when the supply is normal.

Fig. 2 shows a modification of the invention just described7 in which two central lues A A are omittedso that the; lire gases reach tiues B without'any previous cooling. The danipers 7i: and Z also are pivoted on opposite sides from the position had by them in Fig. l, As a consequence of this modified arrangement the fire gases may reach the superheater at a somewhat higher temperature than is the casewith the arrangement shown in Fig. 1. `It will be noted further that the gases instead of dividing between ylines B B and C Cand then passing otl through the single tlue D D as in Fie. l will now pass downwardly through the single iiue B B and divide upwardly between the dues C C and D D.

The line walls (gli, c, d, etc., are preferably, as has been dcscribedabove7 of water tubes arranged in wall formation with ends suitably separated at top and bottom. to allow the tire gases to pass. Such an arrangement of water tubes to constitute walls is now fairly well known. Insteadct using' water tubes for such fluewalls, however, ywe may, if we desire7 constitute them of tire brick, asbestos or any other ediiivalent material, without depart-ing from the spirit ot our invention.

Many modifications in detail of the invention herein described may be made, and *in showing only' two arrangements we do not by any means wish to limit ourselves to such, but wish it to be understood that all variations ot' said described structure are consi( :red by us as part of our invention so .long as they are descibed by the claims appended hereto. An advantage of our im-l proved arrangement ot' super-heater as herein set l'orth is that the water tubes employed may be the usual small. tube which would be einj'iloyer-l for the water tube boilri without superlwatcr. `While we prefer such usu'al tubes, may, it desired, use tubes of larger size without departing from the spirit of our invention,

die claim as our invention:

l. ln a water tube boiler comprising upper and. lower drums connected by sets'oi 'water tubesv cach ot which sets is arranged to provide a plurality of lines, a set of said tubes having some tubes bent away from others so as to provide a special flue adapted to be paralleled with an adjacent liue of the same set, a superheater within said special flue, and a regulating damperat Ian end of said parallel lues.

2. In a Water tuber boiler comprising upper and lower drumsjconnected. by sets of Water tubes each of which sets is arranged to provide a plurality of ilues, a set ot' said tubes having some tubes bent away from others so as to provide a special flue adapted to be paralleled with an adjacent flue of the same set, a superheater within said special flue, and a regulating damper at an end of said parallel ues, the area of said dainpcr corresponding to the section 'of the special flue and being less than that of the at'oresaid adjacent Hue.

3. In a. water tube boiler comprising upper and lower drums connected by sets of wateritubes, each of which sets is arranged to provide a plurality of tlues, a set of said tubes having some tubes bent away from others so as to provide a special Hue adapted to be paralleled with an adjacent flue of the same set, a superheater Awithin said special flue and a regulating damper at van i end of said parallel iues, said damper being arranged to completely shut ed the superheater flue when in one of its limitingpositions and tol incompletely shut ed the aforesaid adjacent flue when in the other ot its limiting positions.

fl. In a water tube boiler comprising upper and lower drums connected by sets of vater tubes arranged to 'form three serially disposed fiues, the arrangement of the water tubes so as to constitute a lcentral flue such that some tubes are bent away from others to provide a special tiue in parallel with an adjacent tine also formed out of the central flue, a superheater within said special flue, and a damper at an end ot said central flue for :regulatingl the relative amounts ot tire gases which shall pass through the two scctions of' the central flue7 said damper being arranged to completely shut olli the special flue when in one of its limiting positions and to incoinpletely sluit otli` the aforesaid adjacent iiuebelonging to the 'central Hue when in its other limiting position.

ln testimony whercoll we have hereunto set our hands in the presence of two subscribing witnesses.

,VILHELM SCHMIDT.

PETER l'lllOlv/ISEhl. 

